Automatic mechanical gear-shiftitc mechanism



P. W, CRAIG. AUTOMATIC MECHANICAL GEAR SHIFTING MECHANISM.

APPLICATION FILED DEC. 1?. 1918.

1,354,890, Patented Oct. 5, 1920.

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P. W. CRAIG.

AUTOMATIC MECHANICAL GEAR SHIFTING MECHANISM.

APPLICATION FILED DEC. n. 1918.

1,354,890. Patented 001:. 5,1920.

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P W CRAIG AUTOMATIC MECHANICAL GEAR SHIFTING MECHANISM.

APPLICATION FILED DEC. I7, 1918.

Patented Oct. 5, 1920.

5 SHEETS-SHEE'T 3- M (II P. W. CRAIG.

AUTOMATIC MECHA.NI.CALGEAR SHIFTING MECHANISM.

APPLICATION FILED mac. 1?. 191a.

' 1,354,890. 4 Patented 0%. 5,1920.

L aw 5/ 550 rmszs P. W. CRAIG.

AUTOMATIC MECHANICAL GEAR SHIFTING MECHANISM.

APPLICATION FILED 050.47, 1918.

1 ,354,890, Patented Oct. 5, 1920.

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PARLEY l CRAIG, GF ENSLEY, ALABAMA.

AUTOMATIC MECHANICAL GEAR-SHIFTING MEGHANISM.

Specification of Letters Patent.

Patented Oct. 5, 1920.

Application filed December 1.7, 1918. Serial l lo. 267,207.

vmeclmnism,especially adapted for automobiles and all types of motor driven vehicles.

The present general practice of first disengaging the clutch by foot and then shifting the gears into the desired position by means of a lever operated by hand has been found objectionable as it has a tendency to distract attention from the steering of the car and, by necessitating the removal of one hand from the steering wheel, has occasioned many accidents. Moreover, as the operation of the gear shift lever is selective it is often changed into the wrong speed gear and as a result the gears are stripped and the transmission casing is sometimes broken. To overcome these objections, mechanical shifting mechanisms have been designed but their construction has been. so delicate or their ogeration of such doubtful practical value that at the present time none are in general use.

The object of my invention is to design a gear shifting mechanism which extremely simple in its construction, which comprises only a few parts capable of rugged structure and which possesses the distinctivelynovel characteristic of being both automatic and selective in its gear shifting functions. In its automatic functioning my mechanism responds to the clutch pedal and successively in each cycle, shifts the gears from low througl'i intermediate to high speed, then to neutral and finally to reverse,

each change being responsive to a full throw of the clutch pedal. but being unresponsive to a normal disengaging clutch pedal operation necessary for driving conditions not requiringjg a change of the gears. The selective functioning of my invention, which is responsive to hand. control, is necessary because the automatic sequence of gear shifting movements must be changed at times so as to ship any one or more of the changes, this being of peculiar advantage in skipping the reverse when shifting from high through neutral to intermediate or low.

Another feature of peculiar advantage of my invention is that the shifting operation takes place at the exact or criticalmoment when the gears will mesh with the least possible strain. 7

My invention comprises the various novel details of construction and arrangements of parts, which in their preferred embodiments only, are illustrated in the accompanying drawings, and in which Figure 1 illustrates a typical automobile in section showing the manner of mounting the automatic gear shifting mechanism and its controlling and operating parts thereon.

Fig. 2 is a side view of the shifting mechanism as removed from its casing.

l ig. 27 is a top plan. view of Fig. 2; and

Fig. 4 is a sectional view taken on the line 4-4- of Fig. 2.

Fig. 5 is a detail view of the pawl in operating relation with its respective control lever, the view being taken on the section line 5-5 of Fig. 6 through the master lever.

Fig. 6 is an elevation of the pawl carry ing end of the master lever.

Fig. 7 is a top plan view of the hand con trol knob for the pawl setting cam cylinder.

Fig. 8 is a view in section through the pawl setting cylinder, showing the master lever and its pawl in normal or clutch engaged position, the pawls being disengaged from their respective control levers.

Figs. 9 and 10 are diagrammatic views illustrating the different operating positions of a pair of coordinated control levers controlling two of the gear shifting operations.

Figs. 11 and 12 are similar views of the other pair of coordinated control levers which control the other two gear shifting operations.

Similar reference numerals refer to similar parts throughout the drawings.

have illustrated my mechanism as applied to an automobile 1 which is typical of any motor driven vehicle equipped with a clutch lever 2 adapted to rock on an axis 8 and by means of a crank t and suitable transmission elements 5 to operate the clutch 6. A gear case 7 of any suitable type is mounted under the car body and is equipped with any standard type of variable speed transmission gearing, such as is characteristic of motor driven vehicles, and my improved automatic gear shifting mechanism is contained in a casing 8 preferably at-.

tached to the gear case 7.

, made fast in-the hub 18 normal position shown in'F' The mechanism within the gear case 8, which is illustrated more fully in Figs. 2 to at, comprises a frame having a top plate 9 and a bottom plate 10 suitably and rigidly connected by distance bolts ll. This frame isrigidly mounted in the casing by any suitable attaching means and near its center is provided with a main vertical shaft 12, the lower end of which is riveted into the base plate 10 while its upper end projects through the' top plate 9. A sleeve 1% is mounted to turn on the upper end of the shaft 12in suitable bearings in the top frame 9 and its upper end is threaded to receive the nut 13. A rack arm 16 having an arcuate gear segment 1? on its free end is keyed to the sleeve above the plate 9. The lower end of sleeve'lt below the plate 9 is on the upper arm of the yoke-like master lever 19, the lower arm of which master lever is provided with a hub 20 turning on the lower end of the shaft 12 and resting on a bearing boss 21 on the bottom plate 10. The master lever is provided with perforated lugs 22 between which is .pivotally connected one end of the operating rod 23 (see Fig. 1), which passes through a suitable opening in the casing 8 and has its upturned outer end provided with an elongated slot 24 in which engages a pin 25 on the clutch pedal 2. The length of the slot and the normal position of the pin 25 therein is such that the clutch pedal has enough free play to release the clutch sufficiently for ordinary driving purposes without influencing or operating the gear shifting mechanism, but when the clutch pedal is given a full throw, thepin will engage the forward end of the slot 24 and draw the rod 23 forward so as to cause the master lever 19 to swing clockwise from 1, S to operating position shown in Fig. 4.

In the free or open end of the yoke-like 'master lever 19 I mount a vertical bearing pin 26 which at its upperend is received in a socket 27 on the yoke frame and secured in position by a pin 28pass1ng therethrough.

Mounted to turn on this pin 26 are four similar pawls'29, 30, 31 and 32. These pawls are spaced by perforated lugs 33 on the lever through which the shaft 26 passes, and each pawl is engaged by its respective spring 3-i'whicli is made fast in a vertical web 35 which connects the upper and lower members of the yoke lever and carries the lugs The springs tend to hold the pawls in the position of-the pawl 29 in a, but will flex to permit. the pawls to shift to the position of the pawl 30 in this figure. Each pawl comprises a rear end forming a lever engagingtooth 36 and a forward end provided with an outer convex surface 3'? dis- 38 as the pawls move responsive to the oscillation of the master lever 19. The controller cylinder 38 is provided with reduced ends 39 and &0, the former being further reduced and mounted like a step bearing in the bottom frame plate ll) while the upper end ll) is reduced where it passes through the bearing boss ll in the top plate 9 and continues th re above so as to form the hand controller shaft d2 which projects upwardly with ample clearance through the body of the car seat and on its upper end carries a knurled controller knob This knob works above a suitable lined dial plate ll, shown in Fig. 7, and is provided with a pointer tip to which successively assumes position opposite one 01' the other of the live points marked thereon N, ll, 1, L and lit, and respectively indicating the following positions of the transmission gearing, towit: neutral, high, intermediate, low and reverse.

The controller portion of the cylinder 38 is provided opposite each of the several pawls 29, 30, 31 andv 32 with a notch l6 formed by removing a sulliciently large segmental portion of the cylinder opposite each pawl to permit the latter when its respective notch stands opposite it to shift suiliciently in response to its respective spring 8i to bring its lever engaging tooth into op erative position. The notches, as will be more clearly seen in Fig. 4, are distributed about the cylinder as viewed endwise so as to leave one longitudinal uninterrupted neutral Zone or cam surface a? extending the full length of the controller cylinder. The arcs subtended by the several notches are equal and ointly subtend the rest of the circumference of he cylinder not included in the zone 4:7. In effect the controller cylinder in making each complete rotation will advance live equal steps and with each step will present one of the notches or the neutral zone in pawl controlling position.

The step by step movement of the controller cylinder can be ell'ccted both automatically and manually, the manual advance of the cylinder being controlled by the knob 43 which will turn the shaft 42 and with it the COHtl'OllGi cylinder 38. In order to force the cylinder to assume its successive operating positions I mount fast on the shaft a2 a ratchet wheel 48. see Fig. 3, having live equi-distantly spaced ratchet teeth thereon which are engaged on one side by a roller 49 journalcd in the yoke end of a springpressed rod 50 which is slidubly mounted in brackets 51 on the top bearing): plate 9 and is prov ded with a collar 52 against which a coil spring 53 interposed between it and the bracket yn'esscs, and by forcing the roller against the ratchet teeth I tend to bring the shot to rest at one or the other of its five operating positions.

The automatic mechanical means for shifting the controller cylinder comprises a gear wheel 5% mounted on the plate 9 and meshing on one side with the rack 17 and on the other with a segment 55 which is made fast to or is formed integral with the ratchet wheel 4:8. On this segment 55 I mount a pawl 56 which is normally pressed by a spring 57 against the ratchet wheel 48 with the result that each oscillation im- .the sleeve lat and arm 16 through the gears 17, 54c and 55 and through pawl to advance the ratchet wheel 18 one step. As the segment 55 nears the completion of its driving stroke a pin 58 on. the pawl 56 will engage the ram surface 59 of the throw-out stop plate 60 attached to the top plate 9 and elevated enough to let the pawl. pass beheath it but against which the pin 58 will strike causing the pawl to disengage from the ratchet 48 and remain in this position while the clutch pedal stands in clutch engaged position and has shifted the several parts of the mechanism accordingly. This throw-out stop thus in the engaged position of the clutch will free the ratchet wheel so that the controller cylinder may he moved backward or forward by the lrnob d3 and placed in any position that the operator may wis that the next operation of the clutch pedal to release the clutch will shift the g Mrs to that position to which the controller cylinder was set. ltlach full op ation of the clutch pedal thus automatically gives the segmental gear a full stroke a the ratchet wheel 48 one toot controller cy inder to its opera o ion next in order and shifts the trz'insmission gears to the position last indicated by the knob tip 45.

The drawings illustrate an apparatus adapted to worlr the standare four speed transmission such is most generally used at present, "ould it he desired to adapt the vtheap iaratus to control a transmission havber of teeth on the ratchet wheel L8. Also the pawl operated controllevers for effecting the gear shifts would proportionately be increased.

1 illustrate four pawl operated control levers 61, 652;, 63 and 6% which are corretwo pairs comprising re and 62 and the lovers he and lleferrinsgnow to the levers 6i and 62 it will he seen that both are mounted to turn independently on the shaft that each is provided at its free with a pawl engaging head having; a convert surface 65 terminat' g at one end at the base of a detent or shoulder 66. The

.1. iii

shown it will he seen i comps r. o? l igs. 8, 9 and l0 that as either lever or 692; is thrown in one direction by respective pawl 29 or 30 the other lever of the pair is moved in the opposite direction beyond its normal position shown in Fig. 8. The link 71 and the arm 69 are con nected to the rod 3 which is adapted to shift the gears to high speed and second or ii'itermediate sp l positions. The leve 63 and 64: are respeetively to levers 61 and and the arm 79 of the lever (i l is connected by means of a link "71. to a shifting arm 69 that is (Bonner ed by gears 67 and 68 and serves to operate a gear shift rod 73" controlling the low speed and reverse shifting movements of the transmission gears. 'lhe arm 69 is proviced with an elongated huh 7% (see Fig. 2), which. hears on the v arm car which has a shorter hub hearing which rests on the base plate 15'), the two hubs being held rotatahly in position on the shaft by means of a nut T5 screwed thereon.

its the master lever 19 is oscillated with each full clutch releasing stroke of t 4 clutch pedal it advances the several pai 29, 30, 31 and 32 toward the controller cylinder 38, i. 6., moves them from their normal clutch engaged posi ions as illustrated in 8 to the position shown in Fig. l. As the several pawls are thus vanced it will he seen that the surfaces 3? of all of these except the pawl 29 i) will contact with the periphery of the cylinder, whereas the pawl 29 under tension of its respective spring 34; will engage in its respective notch i6 and in doin so its teeth 36 will be free to snap against the surface 65 on the head of the lever 61 and assume operative position. The teeth 36 on the other three pawls will be held by their engagement with the true surface of the cylinder 35?- away from their respective control heads and in what ll term inoperative position. As the lever is allowed to move to clutch engaging position, the master lever 19 shifts from the position in Fig. 4i to the position in Fig. 8, and in doing so the pawl that has shifted into engagement with the lever 61. will strike the tooth 66 on the latter and carry itto the position shown in Fig. 9. This movement of the lever an act ing through the gears 67 and 68 will. move the shifting arm 69 rearwardly and thereby through the gear shift rod 73 will shift the gears to reverse position and at the same time through link 71 and arm T2 will move the control lever 62 as an idle element fen ward of its initial position. The next re leasing movement of the clutch will again shift the. master lever 19 from the position shown in Fig. 8 to that shown in Fig. i, and in doing so its web 35 will pick up the retracted lever 61 and aovance it to neutral position, and this movement through the gearing 67 and 68 and link 71 will draw back the'lever 62 to its initial position. in the meantime however through the ction of the gearing described, the controller cylinder will have advanced one step, and in doing so will present a notch l6 into posi tion opposite the pawl 80.

The next clutch engaging movement or the pedal will rock the masts lever, cans" the pawl 30 to pick up the lever *2 move itt'othe position shown in which through the instrumentalities scribed will shift'the lever 61 forward and will move the shift rod 73 so as to change the gears from neutral to low speed. The clutch releasing movement will shift the control levers to neutral position and present the cylinder in position with the notch opposite the pawl 63 which will cause the pawl 31, as it moves responsive to the he; clutch engaging movement, to shift the levers 63 and G l'to the positions shown in Fig. 11, and by means of the shift rod 73 to shift the gears to intermediate speed. The next clutch releasing movement will return all control levers to neutr and present the controller cynotch opposite the pawl 32 so ceeding clutch engaging movc cause this pawl to engage lever (i i a it to reverse the position of levers 63 and or from the position in Fig. 11 to that shown in Fig. 12 and to shift the gears from intermediate to high speed. The next clutch releasing movement will return all control levers to neutral position and present the con.- troller cylinder with its neutral zone in pawl engaging position where it will. be seen that the rod73 is shiftedto position midway between the positions shown in Figs. 9 and 10,, and'in like manner the rod 73 will be shifted midway between the positions shown in Figs. 11 and 12. The

' clutch engaging movement of the master lever will not disturb the position of the control levers nor of the rods 73 and 73 due to the fact that all of the pawls 29, Sl and 32 are held out of lever engaging position by their engagement with the true sun 7 face of the cylinder or its neutral zone. The

nae a soc were in neutral position the knob 4C3 was turned by hand to ship the reverse position and present the controller cylinder 88 in position to cause the slr ting of the gears to low, intermediate or high speed position as may be desired with the next clutch engaging movement. lt will be understoi'id that the controller cylinder may be shifted at any time to any point in the cycle of operation to bring the transmission gearing into the c esired mesh with the next clutch engu fs;

movement thus giving the :rmiratiis as :iiill c Q l L freedom of manual control and as complete select 'ty as exists in any iiiochiinicci; gear shirting apparatus, but at the some time the transmission gears will. automatically in the manner described respond to full clutch 0pc LlOZlS and follow i'liro gjh the no mal sequence oi "our shifting steps in driving ope ions and (herogreatly simplify the attention nec essary for shifting the gears.

It should be espec illy noted that each operation of the clutch pedal to dmeugago it acts through the web 35 to engage and move the control levers and transmiss on gears into neutral position before the clutch engaging movement of the pedal effects the gear change and this clutch ong movement being responsive to spring action will. effect the shifting of the gears in the manner that will have the least possible tendency to strip or injure the gears, it being dos-:iralm tl it the teeth should be snapped into ongagement with a quicl: positive lllilYQlllllll) for best results.

It will be understood that the detail construction of the master lever, the controller cam and the pawl operated control levers may be substantially varied without departure in principle from the substance of my invention, which is not limited to such detail construction but covers such changes as may properly come within the scope of the ap Jended claims.

Having thus described myinvention,what I claim as new and desire to secure by Letters Patent is 1. The combination with variable speed transmission gearing, of a plurality of gear shifting members, a master actuator for said members and its operating means, a selective transmission means between said actuator and members, a controller means for the selective means, and means to autoniaticully shift said controller means with each operation of said actuator.

2. The combination with *ariablc speed transmissiongearing, of a plurality of gear shifting members, a master actuator for said members and its operating means, :i selective transmission means between said actuator and members, a controller means for the selective means, means to automatically shift said controller means with each operation of said actuator, and means to shift the controller means independently of said automatic shifting means.

3. The combination with variable speed transmission gearing, of a plurality of gear shifting members, a master actuator for said members, means to operate suit. actuator by the clutch pedal, and a selective traninnis sion means between said actuator and members, comprising as elements a controller means, and agencies, one automatic and the other selective, which jointly control the positioning of said controller means.

l. The combination with variable speed transmission gearing, of a plurality of gear shifting members, a master actuator for said members, means to operate said actuator by the clutch pedal, and a selective transmis sion means between said actuator and members, comprising as elements a controller means, and agencies, one pedal controlled and the other manual controlled for shifting said controller means.

The combination with variable speed transmission gearing, of a plurality of gear shifting; members, a master actuator for said members and its operating means carrying pawls, a controller cam tor said. pawls adapted to position them one at a'time in operative position to engage and move its respective gear shifting; member, and clutch pedal controlled means to move the actuator and shift said controller cam step by step.

6. Multiple speed mechanism and a controller therefor including a speed changev actuator, a selector automatically advanced step by step by said actuator, and means movable with the actuator and positively controlled by the relative position of the lector thereto, for effecting the speed change appropriate for the position of the selector.

7. Multiple speed mechanism and a con troller therefor including a speed change actuator, a selector automatically advanced step by step by said actuator, means positively controlled by the selector, for effecting the speed change appropriate for the position of the selector, and manual means to supersede the automatic step by step positioning of said selector and set it for any desired speed change.

8. The combination with variable speed transmission gearing, and means for shifting the gearing, of an actuator, meansautomatically responsive to the movements of said actuator to shift said gearing through a predetermined sequence of different operating positions, and a hand control means to modify selectively the sequence of different operating positions of said gearing.

9. The combination with variable speed transmission gearing, of means for shifting the gearing comprising a master lever and means to reciprocate it, a plurality of pairs of operating levers, means coupling the units of each pair of operating levers to cause them to move in reverse directions from neutral position, a gear shifting element controlled by each pair of operating levers, means on the master lever as it moves in one direction to move all operating levers to neutral position, and cam controlled means on the master lever adapted as the latter moves in a reverse direction to enand move a predetermined operating lever, as and for the purposes described.

10. in a gear shifting mechanism, pairs of operating levers, gear shifting elements controlled by eachpair of levers, means coupl in the units of each pair of levers to earn them to move in reverse directions i as it moves in one direction to shift all operatin levers to neutral position, a pawl carv the master l ver for moving each operating: lever, a controller cam :tor the pawls adapted to move them one at a time into operating position to engage and move its respective o', erating lever along with the movement of the master lever, and manual zans to adjust the controller cam to bring the desired 1 and into operating; position.

11. in a near shifting mecnanism, pairs of operating levers, gear shifting";- elements controlled. by said pairs of levers, means coupling: the units of each pair of levers to cause them to move in reverse directions from neutral position, a master lever adapted as it moves in one direction to shift all operating levers to, neutral position, a pawl carri d by the master lever for each operatinr; lever, a controller cam for the pawls adapted to move them one at a time into operating position, the pawl in operating position being" adapted to engage and move its respective operating lever along with the return movement of the master lever, manual means to adjust the controller cam to bring the desired pawl into operating position, and yieldable set means to bring the controller cam to rest in one or the other of its operating positions.

12. in a gear shifting; mechanism, the combination of a master lever and a plurality of gear shifting agents inde aendently controllable thereby, of rotatable controller cam having a plurality of cam tacos equidistantly distributed about its periphery, means responsive to each of said surfaces which is adapted in response to a movement of the master lever to effect a predetermined shift of the gears, clutch pedal controlled means to rotate said cam step by step from one to another of its operatine: positions, and manual means to advance the cam to skip any desired number of steps, substantially as described.

13. Tu a near shifting); mechanism, a clutch pedal operated master lever, pawls carried by said lever, a controller cam for said n neutral position, a r aster lever adapted pawls, means operable by the pawls when they assume operating position under control of said cam to shift the transmission gears, said master lever being adapted responsive to the clutch disengaging move ment to present its pawls to the cam and on the clutch. engaging movement of the pedal to shift the transmission gears by means or the pawl in operative position, and means re sponsiveito the clutch engaging movement of the clutch pedal to shift the cam to a new operating position.

14. In a gear shitting mechanism, a clutch pedal operated master lever, pawls carried by said lever, a controller cam for said pawls, means operable by the pawls when they assame operating position under control of said cam to shift the transmission gears, said master lever being adapted responsive to the clutch disengaging movement to present its pawls to the cam and on the clutch engaging movement of the pedal to shift the transmission gears by the pawl set by the cam in operative position, means responsive to the cliitch engaging movement 01 the clutch pedal to shift the controller cam to anew operating position, said means comprising a'pawl and ratchet feed to the cam, and means to disengage the pawl and ratchet at the completion of each cam shifting operation.

15. in a gear shifting mechanism, a clutch pedal operated master lever, pawls carried by said lever, a controller cam for said pawls, means operable by the pawls when they assume operating position under con trol of said cam to shift the transmission gears, said. master lever being adapted responsive to the clutch disengaging movement to present its pawls to the cam and on the clutch engaging movement of the pedal to shift the transmission gear by means of the pawl in operative position, means responsive to the clutch engaging movement of the clutch pedal to shift the cam to a new operating position, said means comprising a pawl and ratchet feed to the cam, means to disengage the pawl and ratchet at the com pletion of each cam shifting operation, a handle to shift the cam at will. when the pawl and ratchet are disengaged, and yieldable means to bring the cam to rest in one or the other of its operating positions, substantially as described.

16. Ma tiple speed mechanism and controller means therefor including a selector "for the various speed controls having a visible indicator, and a speed change actuator movable in one direction to engage and be set by said selector and in a reverse direction for effecting the speed control indicated by the selector and controlled by its setting.

in testimony whereof I allix my signature.

PARLE W. CRAIG.

Witness NoMin VVnLsH. 

